🏹 Catapult Academy — Alice & Isaac's Study Guide

⚔️ What Is a Catapult?

A catapult is a type of siege engine — a machine built to hurl objects (called projectiles) through the air using stored energy. Ancient armies used catapults to attack enemy walls, towers, and soldiers from a safe distance.

\n Key Idea: A catapult stores energy (like tension, gravity, or torsion) and then releases it quickly to launch a projectile.\n

\n\n

\n \n

Basic catapult anatomy — pivot, arm, counterweight, and projectile

\n\n

The word \"catapult\" comes from the Greek words kata (against) and pallein (to hurl or toss). Catapults were among the most important military machines in the ancient and medieval world!

🏛️ History of Catapults

\n ~400 BCE — Ancient Greece: The First Catapults\n The Greeks in Syracuse (Sicily) invented early catapults called gastraphetes (belly-bows) — giant crossbow-style weapons. Dionysius I of Syracuse used them in battle. Phillip II and his son Alexander the Great improved catapult technology greatly.\n

\n ~300 BCE — Ancient Greece & Rome: Torsion Catapults\n Engineers discovered that twisted rope or animal sinew (torsion) stored enormous energy. This led to the ballista (fires bolts) and onager (throws stones). Roman armies used these to conquer much of Europe.\n

\n ~600 CE — Early Middle Ages: The Trebuchet Arrives\n A new type using a heavy counterweight — the trebuchet — was developed in China and the Middle East. It was far more powerful than torsion designs.\n

\n 1000–1300 CE — Medieval Europe: Catapults Dominate Warfare\n Trebuchets were used in famous sieges across Europe and the Holy Land. The largest trebuchets could hurl 300-pound stones over 300 yards! Castles were built taller and stronger specifically to resist them.\n

\n ~1300s CE — Decline: Gunpowder Changes Everything\n When cannons firing gunpowder were introduced, catapults gradually fell out of use. However, trebuchets were still used occasionally as late as the 1500s.\n

\n Today — Catapults Live On!\n Modern aircraft carriers use catapult systems to launch planes. Engineers and scientists build catapults to study physics. And students like you compete with them in Science Olympiad! 🎉\n

The largest trebuchet ever built in the medieval period, \"Warwolf,\" was constructed by King Edward I of England in 1304 to attack Stirling Castle in Scotland. It was so enormous that the castle surrendered before it was even finished!\n

🗂️ Types of Catapults

There are several major types of catapults. Each one works using a different source of stored energy. Let's meet them all!

Ballista

Like a giant crossbow using twisted rope (torsion) to fire bolts or stones in a flat, direct path. Used by Greek and Roman armies. Very accurate.

Onager

Uses a twisted bundle of rope or sinew. Has a single throwing arm with a sling or cup. Named after the wild donkey for its kick! Used by Romans.

Trebuchet

Uses a heavy counterweight on one end of an arm to swing the other end — and the projectile — upward at high speed. Most powerful medieval catapult.

Mangonel

A simpler torsion catapult with a cup-shaped end on a wooden arm. Easier to build than a trebuchet. Used widely in the Middle Ages for hurling stones.

Springald

An indoor version of the ballista, designed to fit inside towers. Fired bolts horizontally. Used for defending castle walls.

Gravity Catapult

Uses only the force of gravity — no twisted ropes. The trebuchet is the most famous example. Gravity catapults are very consistent and powerful.

Perrier

Powered by a team of people pulling ropes on one end of the arm — no counterweight needed. Also called a traction trebuchet. One of the oldest and simplest catapult designs, used across the Middle East and medieval Europe.

⚙️ DETAILED VIEW: The Onager — Roman Torsion Catapult

\n \n

\n 1\n Stone & Cup
The cup at the arm tip holds the stone before launch.\n

\n 2\n Throwing Arm
The long wooden beam that snaps upward when released.\n

\n 3\n Pivot Axle
The fulcrum (hinge) the arm rotates around.\n

\n 4\n Torsion Bundle
Tightly twisted rope or sinew — stores energy like a wound-up rubber band.\n

\n 5\n Stop Beam
A padded crossbar that halts the arm, snapping the stone forward.\n

\n 6\n Wood Frame
The sturdy chassis holding all parts together and keeping the machine stable.\n

\n 7\n Wooden Wheels
Large spoked wheels let soldiers move the heavy onager across the battlefield.\n

When the torsion bundle releases, the arm snaps upward and the stop beam halts it — launching the stone in a parabolic arc.

⚙️ DETAILED VIEW: The Perrier — Human-Powered Traction Catapult

\n \n

\n 1\n Stone & Sling
The sling pouch at the long arm tip holds the stone projectile before release.\n

\n 2\n Long Arm
The longer side of the beam — this end swings up fast and launches the projectile.\n

\n 3\n Pivot Axle
The fulcrum where the beam rotates. The arm spins around this point when the crew pulls.\n

\n 4\n Short Arm
The shorter side of the beam, where the pull ropes are attached. The crew pulls this end down.\n

\n 5\n Pull Ropes
Ropes tied to the short arm. Soldiers grab and yank these downward to fire the catapult.\n

\n 6\n Pulling Crew
A team of soldiers pulls in unison, replacing the heavy counterweight used by a trebuchet.\n

\n 7\n Wood Frame
The sturdy base and support posts that hold the pivot axle in place during firing.\n

\n 8\n Wooden Wheels
Allows the perrier to be moved and repositioned quickly around the battlefield.\n

The perrier needs no counterweight — a team of soldiers pulling the ropes provides all the power needed to launch the stone.

\n\n

⚗️ The Physics Behind Catapults

Catapults are amazing examples of physics in action! Here are the key concepts:

🔋 Stored Energy (Potential Energy)

Before launch, a catapult stores energy. This can be:

Elastic/Torsion energy — from twisted ropes or sinew (like a wound-up rubber band)
Gravitational potential energy — from a heavy weight raised high (like the trebuchet's counterweight)
Spring energy — from bent wood or metal

💨 Kinetic Energy (Moving Energy)

When released, stored energy becomes kinetic energy — energy of motion. The arm swings and transfers energy to the projectile, which flies through the air.

📐 Projectile Motion

Once airborne, a projectile follows a curved path called a parabola. Two forces act on it:

Inertia — keeps it moving forward
Gravity — pulls it downward

The best launch angle for maximum distance is 45 degrees!

⚖️ Lever Principle

Most catapults work as a lever. A lever has three parts: the fulcrum (pivot point), the effort arm (where force is applied), and the load arm (where the object sits). In a trebuchet, the longer arm moves faster — giving the projectile more speed!

A trebuchet with a 1-ton counterweight can hurl a 100-pound stone at over 100 miles per hour — faster than most highway speed limits!

📊 Catapult Comparison Chart

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

Catapult Type	Energy Source	Origin	Projectile	Best Feature
Ballista	Torsion (twisted rope)	Ancient Greece (~400 BCE)	Bolts, arrows, stones	Very accurate
Onager	Torsion	Ancient Rome (~300 BCE)	Stones, incendiary pots	Compact, mobile
Mangonel	Torsion	China / Middle Ages	Stones, debris	Simple to build
Trebuchet	Counterweight (gravity)	China, ~600 CE	Heavy stones, barrels	Most powerful
Springald	Torsion / spring	Medieval Europe	Bolts, small stones	Fits in towers
Perrier	Human pull (tension)	Middle East / Europe	Stones	No heavy counterweight needed

📝 Key Vocabulary

ProjectileAn object launched through the air by a catapult or other machine.

TorsionEnergy stored in twisted rope, sinew, or other material.

CounterweightA heavy weight that powers a trebuchet by falling.

LeverA simple machine with an arm and a pivot (fulcrum) used to multiply force.

FulcrumThe pivot point of a lever or catapult arm.

TrajectoryThe curved path a projectile travels through the air.

SiegeA military strategy of surrounding and attacking a fortified place.

ParabolaThe arc-shaped curved path of a projectile under gravity.

Kinetic EnergyEnergy an object has because it is moving.

Potential EnergyStored energy waiting to be released.

SinewAnimal tendon used as strong, stretchy rope in ancient catapults.

SlingA pouch on the end of a rope that holds the projectile in a trebuchet.

InertiaThe tendency of a moving object to keep moving in the same direction.

Siege EngineAny large military machine used to attack fortifications.

GastraphetesThe earliest Greek catapult — essentially a giant crossbow.

WarwolfThe largest trebuchet in history, built by King Edward I in 1304.

🏰 Famous Catapult Moments in History

Siege of Syracuse (214–212 BCE): Archimedes designed catapults and other war machines to defend Syracuse against Roman attack. His catapults were so effective they terrified Roman soldiers!
Julius Caesar's Campaigns (50s BCE): Roman legions used ballistae and onagers to help conquer Gaul (modern France) and Britain.
The Crusades (1096–1270s CE): Both Christian crusaders and Muslim defenders used trebuchets in siege warfare across the Middle East.
Siege of Stirling Castle (1304): King Edward I built \"Warwolf,\" the greatest trebuchet ever made, forcing the Scottish garrison to surrender.
Mongol Conquests (1200s CE): Genghis Khan's armies used trebuchets (operated by captured Chinese engineers) to smash city walls across Asia and Europe.
Modern Aircraft Carriers: Today's carriers use electromagnetic or steam-powered catapults to accelerate jets from 0 to 165 mph in just 2 seconds!

During some medieval sieges, attackers launched beehives, diseased carcasses, or burning barrels of tar over enemy walls using catapults — some of the earliest examples of biological and chemical warfare!

✅ Quick Review — Remember These!

\n 🏆 The trebuchet is the MOST powerful catapult type — powered by counterweight gravity, not torsion.\n

\n 🎯 The ballista is the MOST ACCURATE — fires like a giant crossbow, good for targeting.\n

\n 📅 Catapults were invented around 400 BCE in ancient Greece.\n

\n ⚖️ All catapults use a lever principle — a pivot point, an effort, and a load.\n

\n 📐 The ideal launch angle for maximum range is 45 degrees.\n

\n 🔢 The Warwolf (1304 CE) was the largest trebuchet ever built — by King Edward I of England.\n

Ready to test your knowledge?

\n\n

⚔️ Catapult Knowledge Challenge

Test what you've learned with 40 questions covering catapult history, types, physics, and famous battles. Take your time and think carefully — you can do it!

👥 Alice & Isaac — compete to see who scores higher!

\n \n

\n\n

\n Question 1 of 40\n Score: 0\n

\n\n

\n\n\n\n`;\n\n return new Response(html, {\n headers: { \"Content-Type\": \"text/html; charset=utf-8\" }\n });\n}","deleted","label","scioly2",[105],"permalink","https://www.val.town/x/jovenis/scioly-catapults/code/main.ts","extension","actionData","errors"]